The experimental drug Eliquis prevented blood clots in the legs and lungs and kept them from recurring, according to a new study. Patients who took the medicine — which is made by Pfizer Inc. and Bristol-Myers Squibb — were 81% less likely to have symptoms of a clot or die than those who received a placebo, according to findings published in the New England Journal of Medicine. In June, federal regulators rejected Eliquis as a treatment to reduce the risk of stroke in people with a type of heart arrhythmia. The New York-based companies are expected to hear by March whether the agency will approve the drug. Should Eliquis gain clearance, it could generate sales exceeding $4 billion, according to analysts.